Curtain cord equalizer



March 17, 1959 s. R; BOND 2,877,527 CURTAIN coma EQUALIZER Filed May 25,1954 2 Sheets-Sheet 1 I6. FIG.5 Sam? HIS ATTORNEYS March 17, 1959 s. R.BOND 2,877,527

CURTAIN CORD EQUALIZER Filed May 25, 1954 2 Sheets-Sheet 2 F|G.|O FIG.

47 35 52 INVENTOR SCOTT R.BOND F|G.|2 F|G.|3 FIG; aim/M HIS ATTORNEYS2,877,527 CURTAIN CORD EQUALIZER Scott R. Bond, North Plainfield, N. J.,assignor to Levolor orentzen, Inc., New York, N. Y., a corporation ofNew York Application May 25, 1954, Serial No. 432,284 7 Claims. (Cl.24-123) This invention relates to a cord equalizer that is used forequalizing the two lift cords of a curtain that is raised by thesimultaneous, equal movement of two such cords. The term curtain is usedherein in its broad sense of a hanging device which blocks or obscuresthe view, e. g., the view through a window.

Among the specific types of curtains which are customarily raised by twolift cords are porch shades and Venetian blinds. A porch shade is in thenature of a hanging mat and is often made with thin strips of wood orbamboo which are flexibly held in edge-to-edge relation by interlacedstrings that act as warp. It and similar shades wardly under the actionof two lift cords under the bottom edge of the shade. in a Venetianblind, the two lift cords pull the bottom bar of the blind upwardly, andthe bottom bar picks up the slats one after the other.

The two lift cords of a curtain are customarily reeved to exert theirraising. action at the bottom of the curtain near the two vertical edgesthereof, respectively. The two lift cords must be moved in unison tokeep the bottom of the curtain horizontal as the curtain is raised. Forthis reason, it is common practice to connect the two lift cordstogether with an equalizer, which is usually located some distance abovethe point where the two cords are grasped by the operator to raise thecurtain. In many installations, the two lift cords are the two branchesof a long cord that is doubled back upon itself below the point Wherethe operator grasps the cords, each branch constituting one lift cord ofthe curtain.

Equalizers used heretofore have had various disadvantages orlimitations. Some could not be applied to the cords as quickly as isdesirable, and some could only be applied'by threading the cords throughthe equalizer. Some could be applied only with the aid of tools,sometimes special tools. Some could not be removed from the cords andthereafter replaced. With some the relative position of the two cordscould not be readily adjusted, and the position of the equalizer on thetwo cords could not be readily adjusted. Some did not keep the two cordsreliably equalized when a strong pull was exerted by the operator on onecord only. Some were more exensive than was desirable, and some were ofunattractive appearance.

Among the objects of the present invention are to provide a cordequalizer of improved construction and appearance, the equalizer beingparticularly characterized by the security of its gripping of the cords,by the ease with which it may be applied to the cords, adjustedlongitudinally thereof, and removed therefrom; to provide acord-equalizer that may be readily applied to the cords and removedtherefrom manually without the use of special tools, the equalizer beingreusable, as in reeving new lift cords in a curtain; to provide a cordequalizer in which the lift cords may be laterally inserted thereintowithout the necessity of threading the lift cords therethrough; toprovide a cord equalizer which may be rapidly and inexpensivelymanufactured by molding from a plastic material; and generally toimprove-cord equalizers of the type described.

. Further objects and objects relating to details and economiesofconstruction, operation, and use will more definitely'appear from thedetailed description to follow:

which are looped may be raised by rolling the shade up- 2,817,522?Fatented Mar. 17, 1959 My invention is clearly defined in theappendedclaiinis' Where parts are, for clarity and convenience, referredto on the basis of their oriented position shown in the accompanyingdrawing, no limitation as to the use of the cord equalizer in othersuitable positions is to be implied, since the equalizer may be invertedand may also be applied to the lift cords from either the front or therear. Also in both the description and the claims, parts at times may beidentified by specific names for clarity and convenience, but suchnomenclature is to be understood as having the broadest meaningconsistent with the context and with the concept of my invention asdistinguished from the pertinent prior art. The best modes in which Ihave contemplated carrying out my invention are illustrated in theaccompanying drawing forming part of this specification, in which:

Fig. 1 is an elevation of a curtain, specifically a Venetian blind,showing a cord equalizer in accordance with a first embodiment of thepresent invention applied to the lift cords of the blind. A portion ofone of the ladder tapes of the blind is broken away to show one of thelift cords extending to the bottom bar of the blind.

Figs. 2 through 5 show the equalizer of Fig. 1 on a larger scale. Fig. 2is a perspective showing the rear of the equalizer per se. Fig. 3 is arear elevation showing the equalizer applied to the lift cords. Fig. 4is a View taken on the line 4-4 of Fig. 3. Fig. 5 is a cross sectiontaken on the line 55 of Fig. 3.

Fig. 6 is an exploded view in perspective of a second embodiment of thecord equalizer of the invention.

Fig. 7 is a front elevation of the body of the equalizer of Fig. 6. v

--Fig. 8 is a rear elevation of the cap or cover member of the equalizerof Fig.6.

' Fig. 9 is a front elevation showing the cord equalizer of Fig. 6applied to a pair of lift cords.

' is such that a pull on either one Fig. 10 is a view on the line 10-10of Fig. 9.

Fig. 11 is a cross section on the line 1111 of Fig. 9, the stem of thecap or cover member being shown in plan.

Fig. 12 is an exploded view in section through the cord equalizer of thesecond embodiment, the plane of the section being indicated by the line1212 in Fig. 7.

Fig. 13 is a view in section taken along the same plane as in Fig. 12through the assembled cord equalizer of Fig. 6, the lift cords beingomitted.

Fig. 14 is an enlargement of a portion of Fig. 13, showing the latchingof the cap or cover member to the body of the equalizer.

Fig. 15 is a fragmentary section taken on the line 1515 of Fig. 14.

Referring now to the drawings, the Venetian blind 10 of Fig. 1, which isof the simple-lift variety, has a head bar 11, a bottom bar 12, andslats 14, the bottom bar and the slats being supported by ladder tapes15, 15. The lift cords 16, 16 are reeved through the head bar and passedthrough the slats 14 between the two branches of the ladder tapes 15,15, one lift cord 16 being associated with each ladder tape 15.

' The lower ends of the-lift cords the head bar when the blind is in thelowered position shown in Fig. 1. .The function of the cord equalizer 20of the lift cords 16, 16

be transmitted to each lift cord above the equalizer so that both cordswill be pulled equally and the bottom bar 12 will remain level as it israised. The cord equalizer 20 also serves to keep the lift cords 16, 16hanging in orderly side-by-side arrangement in substantially verticallines, and thus aids in preventing the cords 16, 16 and the loop 17 frombecoming entangled with the ends of the slats 14.

The cord equalizer of the present invention preferably has the single,body part 20 of the first embodiment and the body part 34 and the coverpart 35 of the second embodiment formed as bodies molded from plasticmaterial of suitable mechanical strength and impact resistance. Parts20, 34, and 35 made of molded high-impact polystyrene have proved to beentirely satisfactory. In the first embodiment, shown in detail in Figs.2 to 5, inclusive, the one-piece body 20 has a broad generally fiat base21, the body being preferably mounted on the lift cords with the base 21facing the interior of the room, that is, facing forwardly, as shown inFig. 1. Projecting rearwardly from base 21 is the longitudinallydisposed cord-separating partition member 22, which has a centralthickened diamond-shaped portion 24. Portion 24 is preferably moldedwith a central hole 25 to reduce shrinkage of the molding uponsolidification. Thickened portion 24, which is symmetrical with respectto a longitudinal central plane through and parallel to the sides ofpartition 22, has the oppositely laterally directed cord-snubbing edges26.

- The body 20 is provided on each of the outer edges of the base 21 witha longitudinally curved flange 27 projecting from the base in the samedirection as partition 22, each flange forming, with the partition andthe portion of base 21 adjacent thereto, a longitudinally curvedcordreceiving-and-gripping channel 30. The upper and lower ends of eachof flanges 27, as shown in Figs. 2 and 3, is curved inwardly so that itsfree edge partially overlies the channel, thereby stably retaining thecords in the channels in the positions shown in Fig. 3.

As most clearly seen in Fig. 3, the central portion of each of flanges27 is substantially straight in a direction normal to base 21, to allowthe easy entry of a cord 16 into the central part of the channellaterally through the below the equalizer will equalizer, however,

permanently defaces or mars the cords, which by reason of theirelasticity, regain substantially their original shape when the equalizeris removed from them. No deformation of the equalizer itself isnecessary to cause it to grip the cords. Consequently, the equalizer maybe removed from and reapplied to the same lift cords in a dififerentlocation if desired, or the equalizer may be reused with different, suchas renewed, lift cords.

The second embodiment of the cord equalizer of the invention, shown inFigs. 6 to 15, inclusive, employs a channel-covering cap member whichsomewhat improves the appearance of the equalizer, retains the cords inthe channels somewhat more positively, and allows the equalizer to beapplied to the lift cords from either the back or front of the liftcords without a substantial change in the general appearance of theapplied equalizer. In the following description, it will be assumed thatthe equalizer is applied from the rear of the lift cords, that is,toward the (forward) direction facing into the room.

The equalizer of the second embodiment is designated as a wholegenerally by the reference character 32. Such equalizer has a body(rear) portion generally designated 34, and a cap (front) portion 35.Body portion 34 has a broad circular flat base 36 from which thereprojects forwardly the central vertical cord-separation partition 37having the central thickened diamond-shaped portion 39. Portion 39 isprovided with a central passage 40 and with the symmetrically oppositelylaterally directed cord-snubof the inner surface of each of open side ofthe channel 30. The longitudinal curve of i the central part of eachflange 27 is on a shorter radius than the curve of the outwardlydiverted portion 31 of the cord in the equalizer, and the radialdistance from an edge26 to the central portion of the inner surface ofits confronting flange 27 somewhat exceeds the diameter of cord 16, sothat the cord may readily be entered into the central portion of thechannel. After each of the cords 16 has thus been entered into: thecentral portion of its corresponding channel, the cord may readily becompressed sufficiently for it to snap under the overhanging end 29 ofthe channel. The ends of channels 30 snugly but not tightly receive thecords 16.

The lateral diversion of portions 31 of the cord by edges 26 causes suchedges elastically to indent the inner surfaces of the cords to someextent, and causes the equalizer to grip each cord, when the cord ispulled relative to the equalizer, primarily at three points or zones,that is, at the outer edges of the upper and lower ends of flanges 27,which with partition 22 cause the cords to enter the equalizer and toleave it in substantially parallel vertical position, and the centralcord-diverting-and-snubbing edge 26. The gripping of the cords by theequalizer is such that, if a down pull is exerted upon only one cord 16below the equalizer, the pulled cord is itself more strongly forced intocontact with edge 26 and thus more strongly gripped in its channel, anda part of such pull is transmitted through the equalizer to the othercord 16 above the equalizer, which likewise is more strongly gripped byits channel in the same manner. None of the edges or surfaces engagingthe cords at the the central portions of the 'the cords beneath the endsof bing edges 41. Each lateral edge of the body is provided with a sideflange 42 curved to conform to the base 36 and projecting forwardly fromthe base. The inner top and bottom edges 44 of each of flanges 42 arefairly sharp, as shown in Figs. 6 and 7.

Each flange 42, with its confronting side of the parti tion 37 and theadjacent portion of base 36, forms a curved cord-receiving-and-grippingchannel 45. As in the case of the first embodiment, the radius ofcurvature flanges 42 is somewhat less than the radius of curvature ofthe outwardly diverted portions 46 of the cords, and the radialdistances from the central cord-snubbing edges 41 to the central portionof the inner surface of its confronting flange 42 somewhat exceeds thediameter of the cord 16, so that the cord may readilybe entered into thecentral portion of the channel through the open side thereof. At bothends of the channels there are provided cord-retaining means in the formof transverse members 47 connected to the forward upper and lower edgesof partition 37, so that the ends of members 47 partially overlie thechannels 45.

The body 34 of the equalizer is applied to the lift cords, preferablyfrom the rear, by introducing the cords into channels and then snappingmembers 47 at the ends of the channels. When thus applied, the body 34itself functions satisfactorily as a cord equalizer, the cords beinggripped primarily between the upper and lower inner edges 44 of theflanges 42 and the central cord-diverting-andsnubbing edge 41. As in thecase of the first described embodiment, when one lift cord 16 is pulleddown below the equalizer body, it is more firmly gripped by its channelin body 34 and transmits a portion of the pull to the other cord, whichis also gripped more firmly by the to employ therewith plate 48. Stem 49has equalizer. The cords are stably retained in the body by thecord-retaining means 47.

It is preferred with this embodiment, for the sake of better appearance,added strength of the flanges, and added security of retention of thecords in the body 34, the cap member 35. Such cap has a round flat plate48 of substantially the same diameter as the body 34, the plate having arearwardly directed centrally located mounting stem 49 normal to theplane of a plurality (four shown) of thin, somewhat resilient, radiallydirected longitudinal fins 50 thereon, as shown most clearly in Figs. 6,8, 14 and 15, for

the purpose to be described. The cap '35 is applied to body 34, afterthe cords 16 have been engaged in the body as described, by entering thestem 49 in the central passage 40 in body 34. When the cap is fullyapplied, the rear surface of plate 48 lies in contact with the forwardedges of flanges 42, as shown in Fig. 13, and the upper and lower edgesof plate 48 lie between and at the same level as the cord-retainingmembers 47, as shown in Figs. 9, l0, and 13 and indicated in Fig. 12.

To strengthen the ends of flanges 42 against lateral deflection by thecords, the flanges are provided with forwardly projecting pins 52adjacent the inner edges 44 of the flanges. Such pins are snuglyreceived within the annular groove 54 in the rear surface of plate 48 ofthe cap, as shown in Fig. 13, thereby in effect to connect the flangesat their outboard ends. The central passage 40 in portion 39 of body 34has an annular constricted zone 51 toward the rear thereof. At theconstricted zone 51 the forward surface slopes gradually radiallyinwardly and the rear surface is formed as a sharp shoulder. Constrictedzone 51 extends inwardly of the passage 40 a distance somewhat less thanthe radial height of the fins 50. When the stem 49 has been entered intopassage 40 far enough for the rear ends of the fins 50 to engage theconstriction the fins are progressively deformed by the constriction.Fig. 14 shows the relation between the stem, the fins thereon, and thepassage 40 when the cap is fully applied to the equalizer body. .Becauseof the described configuration of the constriction 51, no undue amountof force is required to deform the fins 50 when the stem is thrust intothe passage as the cap is being applied to the body, since theconstricted portion 51 then deforms the fins 50 with a gradual cammingaction. Withdrawal of the stem from the passage upon removal of the capfrom the body, however, requires a somewhat deforms the fins uponmovement of stem 49 to the left (Fig. 14) with respect to the bodyportion 39. Thus the fins 50 and constricted portion 51 of the passage40 provide a means for securely retaining the cap against fortuitousremoval from the body, but does not prevent the removal of the cap, whendesired, by initially slightly separating the plate portion 35 from thebody 34 as by the insertion of ones fingernail therebetween, and thengrasping the cap by the fingers and pulling it away from the body.

I claim:

1. In a curtain having a pair of lift cords, a cord equalizer at leastpartially embracing said cords and adjustable on and removable from thecords, the equalizer having a one-piece body comprising a generally flatbase, longitudinally curved continuous flanges projecting in the samedirection from the opposite edges of the base and extending along thecords, a centrally located generally straight elongated partition on thebase midway between the flanges and extending at least as far along thecords as the flanges, the ends of the flanges being laterally spacedfrom the partition, the inner surface of each flange and thecorresponding confronting side surface of the partition forming with theintervening portion of the upper surface of the base a longitudinallycurved cordreceiving channel open on one side and permitting entry ofthe cord thereinto through the open side of the channel, and means toretain the cords in the channels, the ends of said flange providing eachof the channels with two cord-diverting-and-snubhing edges on one sidethereof and said partition having midway of its length a formationproviding each of the channels with a corddiverting-and-snubbing edge onthe other side thereof.

2. In a curtain having a pair of lift cords, the combination with saidlift cords of an adjustable and removable cord equalizer at leastpartially embracing said cords, said cord equalizer comprising aone-piece homogeneous body having a pair of curved continuous channelsopen on one side to permit the entry of the cords into the channelsthrough the open sides thereof, the channels extending between twoopposite ends of the body and terminating at both ends thereof, each ofthe channels having one of the cords lying therein, the channels eachhaving snubbing edge diverting the intermediate portion of the cordtherein outwardly from a straight line, the channels directing the cordsin generally parallel side-by-side relation and generally in the sameplane at each end of said channels.

3. A pair of curtain lift cords disposed in side-by-side relationship, adisc positioned adjacent to one face of the pair of lift cords,oppositely-positioned part-cylindrical walls integral with the peripheryof the disc and extending perpendicularly therefrom, one wall beingadjacent to the side of each lift cord with the ends of the wall insnubbing contact with the lift cord and with the center of the walllaterally spaced from the lift cord, and a par tition extendingperpendicularly from the disc and lying between the two lift cords, thepartition extending diametrically of the disc and being at least as longas the diameter of the disc, the partition having on its opposite sidescentrally located protuberances which are laterally directed and whichdisplace the cords away from each other, each cord being normally insnubbing contact with one of the protuberances, and the disc, walls andpartition comprising a cord equalizer which normally grips and holdsboth cords, the cords being adjustable through the equalizer.

4. A pair of curtain lift cords disposed in side-by-side relationship, adisc positioned adjacent to one face of the pair of lift cords,oppositely-positioned part-cylindrical walls integral with the peripheryof the disc and extending perpendicularly therefrom, one wall beingadjacent to the side of each lift cord with the ends of the wall insnubbing contact with the lift cord and with the center of the walllaterally spaced from the lift cord, and a partition extendingperpendicularly from the disc and lying between the two lift cords, thepartition extending diam etrically of the disc and having on itsopposite sides centrally located protuberances which are laterallydirected and which displace the cords away from each other, each cordbeing normally in snubbing contact with one of the protuberances, andthe disc, walls and partition comprising a cord equalizer which normallygrips and holds both cords, the cords being adjustable through theequalizer.

5. An organization as in claim 4 in which the walls and partition formwith the disc open channels into which the cords can be insertedsidewise and be brought into the specified relationships with the endsof the walls, the protuberances and the centers of the walls, and inwhich means are provided at the ends of the channels for normallyretaining the cords therein.

6. An organization as in claim 5 in which the partition is provided witha central hole extending perpendicularly to the disc and a disc-shapedcover overlies the channels and is provided with a pin extending intosaid hole and making holding engagement therewith.

7. An organization as in claim 6 in which the pin is provided withradial fins and the wall of the hole is provided with an inwardlyextending annular bead, and the holding engagement is between the finsand the bead.

References Cited in the file of this patent UNITED STATES PATENTS485,415 Kenyon Nov. 1, 1892 860,189 Chatfield July 16, 1907 914,768Walker Mar. 9, 1909 1,371,932 Przybyla Mar. 15, 1921 1,811,704 BayusJune 23, 1931 1,891,947 Powell Dec. 27, 1932 2,090,860 Bonat Aug. 24,1937 2,246,091 Forstner June 17, 1941 2,460,488 Brunetti Feb. 1, 1949FOREIGN PATENTS 2,397 Great Britain June 17, 1879 UNITED STATES PATENTOFFICE CERTIFICATE OF CORRECTION Patent N00 2,877,527 March 17, 195 9Scott R, 7 Bond It is herebj certified that error appears in the-printedspecification of the above numbered patent requiring correction and thatthe said Letters Patent should read as corrected below.

Column 5, line 52, for "comprising" read comprising: line 66, for"flange" read flanges column 6, line 5,, after "having" insert Signedand sealed this 23rd day of February 19600 SEAL kttestz KARL H AXLINEROBERT C. WATSON Commissioner of Patents Attesting ()Pficer

